Differential truss pad



July 6, 1943- J. H. MASON 2,323,826

DIFFERENTIAL TRUSS PAD Filed ot. 1v, 1940 materially decreasediscomfiture of the as commonly experienced when the area of thePatented July 6, 1943 DIFFERENTIAL TRUSS PAD James H. Mason,

Philadelphia, Pa., assgnor to Chesterman Leeland Company, Philadelphia,Pa., a corporation of Pennsylvania Application October 17, 1940, SerialNo. 361,622

(Cl. 12S-117) 3 Claims.

This invention relates to truss pads for the care of hernia,particularly in cases, for example, where the intestinal protrusionthrough a rupture of the muscles of the abdominal wall is of arelatively small area.

The object of the present invention is to provide a truss pad with aregional face adapted to apply diierential pressures to local areasrespectively of the abdomen, i. e., to the immediate area of the ruptureand to the adjacent surrounding area, to return the protruding intestineto its normal position and to support the abdominal muscles around therupture in order that the muscles may resist recurrence of theprotrusion.

In some cases, it is desirable to apply a rm holding pressure directlyover the area of the rupture and a relatively lighter pressure to thesurrounding area. In other instances it may be desirable to apply thegreater pressure to the surrounding area and the lighter pressure to theimmediate area of the rupture. In either case the truss pad of thepresent invention is adapted to apply the correct degree of pressure toeach area.

Another object of the invention is to provide a regional faced truss padwhich will avoid or patient rupture is small and lies deep below theskin, causing the localized pressure over the rupture to place thesurrounding skin under tension. According to the principles of thepresent invention, the marginal region of the face of the truss padaround the region of the localized high pressure, Will exert a lighterpressure on the strained area of the skin to lessen the tension andthereby decrease the attending discomflture.

Another object of the invention is to provide a regional faced truss padWhich vwill apply a rm holding pressure to an annular area of theabdomen around the area of the rupture and a lighter pressure in theimmediate region of the rupture to hold the abdominal muscles firmlyagainst lateral separation while applying just suf- -ficient pressure inthe region of the rupture to maintain the intestine against protrusionbetween the muscles.

Fig. 3 is a perspective View of the main body portion of the pad; Fig. 4is a perspective view of the pressure localizing applicator; 1

Fig. 5 is a longitudinal sectional elevation of a modied form of trusspad constructed in accord- I ance with the present invention;

Fig. 6 illustrates another modication of the invention;

Fig. 'l illustrates a modied form of pressure localizer; and

Figs. 8 and 9 are plan and side elevational views of still'another form.

The pad shown in Figs. 1 and 2 of the drawing is constructed inaccordance with the principles of the present invention, includes a mainbody portion I, molded or otherwise formed of sponge rubber or othersuitable material, which, for reasons hereinafter set forth, is of afirm but soft, highly resilient character.

In the case of Figs. l, 2 and 3, the pad I is of elliptical shape inplan, semi-elliptical in side elevation, and substantially semi-circularin transverse cross-section, intermediate its opposite ends. The pad,however, as indicated in Figs. 8 and 9, may vary in general contourwithout departing from the spirit of the invention.

At the intersection of the longitudinal and transverse axes a-a and b\-brespectively, of the semi-elliptical solid body I shown in Fig. 1, saidbody is provided with an opening 2 which extends from the plane y-y ofthe crown or top of the pad body I to the base plane of said body I.

Secured to the base surface 3 of the pad body l, is a solid flexibleplate 4, which may be composed of rubber or other suitable material. Theplate 4 is recessed to receive a metal stiifening or foundation plate 5,between the pad body I and the back plate 4. The back plate 4 may besecured to the base surface 3 of the body I, by any suitable means suchas vulcanizing, cementing, etc.

The metal stilening plate 5 provides support for any suitable means 6 bywhich the pad may be secured to a suitable or proper form of spring orelastic belt truss, as dictated by the physique of the patient and/orthe location of the hernia.

The localized pressure applicator I0 (Fig. 4) Vis composed of anysuitable resilient material, such as solid rubber or sponge rubber andincludes a neck or shank 9 which fits into the opening 2 in the body I.The upper end of the applicator Iii is provided with a mushroom head II,which comprises an annular ange I2 adapted tooverlie and rest on the topor crown surface of the body I, around the opening 2.

Preferably the applicator I is secured to the body I in the opening 2and under the flange I2, by a suitable flexible cement to preventseparation of the body I from the mushroom head II.

As shown in Figs. 2 and 3, the body I has smooth rounded recedingsurfaces I3 from the marginal edges of the flange I2 of the applicator Ito the marginal edges of the base plate d; and the marginal edges of themushroom head Il are also rounded and recede toward the body I asindicated at I4.

In that form of the invention shown in Figs. 1 to 4, the applicator I0is composed of firm resilient material and extends from the top planey-y to the base plane where the end 8 of the neck S rests on thestifening plate 5, while the body I is composed of a relatively softermaterial. For example, sponge rubbers of different densitiesrespectively, may be used to give the desired results.

The fiat surface I5 of the applicator I, directly in line with thecross-sectional area of the neck 9, is adapted to be placed against thearea at which the intestinal prctrusion had occurred and to hold theintestine in place against recurrence of the protrusion. The neck 9,being composed of the more solid material and extending completelythrough the body I, of relatively softer material, to the rigid plate 5,localizes the greatest pressure directly in line with the neck 9.

The overhanging flange I 2 of the mushroom head II, in resting on thesofter body I around the neck 9, applies a firm but slightly reducedpressure to the area of the flesh immediately surrounding the centrallocalized high pressure area. The body I, outside and surrounding theflange I 2 applies a still lesser pressure to the flesh. Thus, while thenecessary localization of the greatest pressure at the place required ismaintained, the gradually decreasing differential pressure applied tothe regions surrounding the region of greatest pressure relieves thestrain on the skin in these surrounding areas, thus providing greatercomfort for the patient.

Obviously, the cross-sectional shape of the neck of the applicator, themarginal shape of the mushroom head, and the marginal shape of the bodymay vary to suitthe choice of the desi ser or to suit conditions of thepatient, without departing lfrom the spirit of the invention. Forexample,

the pad may be definitely shape to provide lefits and rights to suitpeculiar conditions. Figs. 8 and 9 illustrate a left side pad. A rightside pad ,would obviously be made in reverse to the struc- .ture of Fig.8.

It will be noted that the axis of the means 6, by which the pad issecured to the belt or spring for supporting the pad in place, is inalignment with the longitudinal axis of the neck of the insertedapplicator I0, whereby the pressure initially produced by the supportembracing the wearers body is applied to the pad in direct alignmentwith the axis of the pressure localizing insert IU.

, In order to reduce the total weight of the pad,

the body Ia `(Fig. 5) may be provided with a cavity I6 of desiredproportions on its under side, adjacent the base plateY fsa andstiffening plate 5cl.. With the body la secured firmly to the base plate4a completely around the marginal edges of the cavity IG, air trapped insaid cavity will tend to act as a pneumatic cushion Within the body I aand permit the pad to adjust itself in a comfortable position againstthe patient. By increasing or decreasing the thickness of the wall ofthe body Ia, and thereby decreasing or increasing the volume of thecavity the degree of pressure exerted by the body Ia may be regulated toa nicety.

The impervious skin which forms on the surfaces of a molded spongerubber body, by contact of the rubber with the walls of the mold, isretained on the wall 2U of the cavity I6, the surface 2| of the openingthrough which the neck Sa of the applicator Ia extends, and on the outersurface of the neck Qa and prevents the escape of air from the interiorof the cavity I6. In some instances, this impervious skin is removedfrom the external surfaces of the truss pads, by bufflng, as is wellknown in the art.

n that form of the invention shown in Fig. 6, the neck Sb is reduced inlength and its lower end does not bear against the stiffening plate 5b.The portion of the resilient material, of which the body Ibis composed,which lies directly under the flange I2b, from said flange to thestiffening plate 5b or base plate 4b supports the mushroom head IIb withsufiicient pressure to suffice in some cases, while the area of the bodyIb lying outside the area of the flange IEb exerts a differentialpressure against the skin around the central region occupied by themushroom head IIb.

In that form of the invention shown in Fig. '7, the neck 9c of themushroom head or applicator IIc is provided with an axial cavity I'I,which forms a diaphragm I8 in the center of the pad, by which arelatively soft center of lower pressure potentiality is provided withinan area of greater pressure exerted by the flange I2C, While the body Icsurrounding the flange I2C may be composed of still firmer material toexert the greatest pressure around the ring of the rupture.

In each instance the underside of the flange I2, 12a, |217, or I2C, asthe case may be, is preferably undercut, i. e., formed with theunderside of the flange at an angle to the plane of the peripheral edgeof the underside of the flange in order to insure firm contact betweenthe peripheral edge of the underside of the flange and the crown face ofthe body surrounding the opening 2 against which the flange of themushroom head bears.

From the foregoing it will be clear that, by making the bodies I, Ia.Iby and Ic of resilient material of one density and the applicators I 0,Illa, Ib and Ic of material of greater or lesser density than that ofthe body with which the applicator is associated a regional face ofdifferential pressures is provided on the pad.

Preferably the pad bodies and the applicators are made of sponge rubberof differing densities, although it will be clear that other materialsof corresponding densities having proportional pressure potentialitiesmay be used without departing from the spirit of the invention, and ifdesired, as illustrated in Figs. 6 and 7, the applicators, for example,may be composed of solid rubber while the associated bodies are composedof sponge rubber or equivalent materials.

The applicator Id, in Figs. 8 and 9, like the applicators of Figs. 6 and9, is preferably of the solid rubber type and formed with a cross-linedface to prevent slipping of the pad relative to the skin. Obviously theapplicators I 0, I 0a, Illb and lilo and/or the associated body elementsI, Ia, Ib and Ic may be similarly serrated or corrugated for the samepurpose.

I claim:

1. A truss pad comprising a body portion composed of inherentlyresiliently material of predetermined density, and an insert on one faceof said pad composed of inherently resilient material of a relativelydifferent density, said insert comprising a head portion protrudingbeyond said face of said body portion, a neck portion located in anopening formed in said body portion, and a ange encircling said neck andoverlying said body portion in contact therewith around said opening 2.A truss pad comprising a body portion composed of inherently resilientmaterial of predetermined density, and an insert on one face of said padcomposed of inherently resilient material of a relatively diierentdensity, said insert comprising a head portion protruding beyond saidface of said body portion, a neck portion located in an opening formedin said body portion, and a ange encircling said neck and overlying saidbody portion in contact therewith around said opening, said neck portionhaving an axial cavity formed therein from one end toward said head andproviding a diaphragm in said head within the confines of the peripheraledge of said flange.

3. A truss pad comprising a body portion composed of inherentlyresilient material provided with an opening extending below the normalcontact face of said body portion, and a diaphragm of inherentlyresilient material extending across said opening at said contact face ofsaid pad.

JAMES H. MASON.

